


Rib-Tickling

by Yoshachu



Category: Undertale (Video Game)
Genre: Bad Puns, Brotherly Love, Domestic Fluff, Fluff, Tickle Fights
Language: English
Status: Completed
Published: 2016-05-26
Updated: 2016-05-26
Packaged: 2018-07-10 08:44:46
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 2
Words: 3,018
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6976093
Author URL: https://archiveofourown.org/users/Yoshachu/pseuds/Yoshachu
Summary: <blockquote class="userstuff">
              <p>What happens when a skeletal monster has had enough of his older brother's laziness and God-awful puns? He gives his brother a rib-tickling experience. What happens when another skeletal monster wants to get revenge on his younger brother? He tickles his funny bone something fierce.</p>
            </blockquote>





	1. Papyrus' Payback

“SANS! GET OFF YOUR LAZY TAILBONE AND HELP ME DO THE DISHES!”

Papyrus threw his head back to scream out to his older brother Sans from the kitchen, standing on a step-ladder to reach the sink in order to wash tupperware. He couldn’t believe it, but some of his leftover spaghetti had gone bad when no one touched it, and he couldn’t help but feel hurt that no one wanted to enjoy his amazing creations reheated.

Sans assured him, though, that he and Frisk, their human friend, just enjoyed Papyrus’ spaghetti when it’s freshly cooked. Regaining his proud persona, the younger skeletal monster proceeded to washing out the tupperware with no hard feelings of his now moldy spaghetti going to waste.

Things would be so much easier, though, if Sans were there to help him like a big brother should...

“SANS!” Papyrus called again, frustration emphasized in his voice. “GET IN HERE NOW AND HELP ME!”

“Can’t, gravity’s taken a hold of me,” the response of the lazy monster replied from the living room. Papyrus bent down to shoot daggers from his sockets at Sans as he laid on the green couch half asleep, his eternal grin still as cheesy and smug as ever.

“Sans, please, aren’t you supposed to play the role as the responsible older brother who acts as the younger’s role model? Because you’re doing a poor job at it.”

“Since when have I ever done any of my jobs, bro?” Sans teased, opening an eye socket halfway to look back at his irritated younger brother. “C’mon, Paps, you should know me by now.”

Grumbling, Papyrus decided better to confront his brother rather than scream from the other side of the house. He placed the half-cleaned tupperware and the rag in the warm soapy water and climbed down the ladder. After drying his bony hands and slipping back on his signature red gloves he stomped into the living room.

“Sans, this laziness isn’t healthy for you. What’s so wrong with helping your brother out at least from time to time?”

“Bro, you know another one of your **pap** -talks aren’t gonna work,” Sans smirked. He giggled as Papyrus threw back his head to scream at the horrible pun.

“SANS! STOP WITH THE PUNS AND HELP ME!”

“Well, **water** you expectin’ from me?” the older brother snickered. “ **Dishesn’t** like the Great Papyrus to ask for help. Are you that **tupperware-y**?”

“STOP IT, STOP IT, _STOP IT_!” Papyrus roared, stomping a foot against the ground. “I HAVE HAD ABOUT ENOUGH OF YOU AND YOUR PUNS, SANS!”

“Hey, no need to get upsetti over moldy spaghetti,” Sans grinned.

“ _NYEEEEEHHH!_ ” Papyrus stomped around the house and shouted in annoyance, which just made his older brother laugh.

“Oh, man, Paps!” Sans chuckled, wiping the beginning of a tear from his eye socket. “Your reactions are really **rib-ticklin’**!”

Papyrus suddenly stopped in his tracks, his eye sockets widening. He hated to admit it – and he surely wouldn’t – but Sans’ horrible pun just gave him an idea that just might work. He slowly turned back to Sans and walked up to him slowly, not taking his gaze off him for a second.

“Heh, what’s wrong, Paps?” the other brother asked with another flash of his signature grin. “Did I **burst your pipes** with that one?”

“Oh, no, you didn’t,” the younger brother replied coolly. He watched Sans’ expression contort with confusion when he didn’t get the reaction he was expecting. “You know how you said my reactions to your God-awful puns tickled your ribs?”

“Uhh... Yeah?”

“Well, if you like your ribs tickled so much, allow me to assist you!” Without warning, Papyrus bent down and shot his arms out to slide them through his brother’s unzipped hoodie to scribble and scrape his gloved fingers over his ribs.

Sans, not expecting this, gasped loudly as his eye sockets widened. Immediately his senses registered and he burst out laughing in response to the ticklish sensations.

“A-AHAHAHAHAHA! PAPS, WHAT ARE YOU DOING?!”

“JUST HELPING OUT, BROTHER!” Papyrus grinned mischievously. He quickly whipped off his gloves to more effectively dig his fingers into Sans’ bony torso through the thin shirt.

“HAHAHAHAHAHAHA! ST-STAHAHAHAP THAT!” Sans laughed. He squirmed around under his younger brother’s wrath as he struggled to push his arms away, his legs kicking out behind him.

“Perhaps I’ll stop under one condition: you stop being so lazy and help me with the dishes!”

“N-NEHEHEHEVER!”

Papyrus smirked as he grabbed Sans’ arms and held them above his head; he knew of his older brother’s weakness as far as physical strength went, so it was no trouble keeping him pinned. He then lifted up his shirt and resumed scraping his fingers along the rib cage.

Feeling bone scrape against ticklish bone only increased the sensasions tenfold, causing Sans to practically shriek with laughter. “GAHAHAHAHAHA! STAHAHAHAP, PAPYRUS! AHAHAHAHAHAHA!”

“I don’t think I will,” Papyrus smirked before wiggling his bony fingers between each rib, grinning widely as his older brother squealed.

“STAHAHAHAHAHAHAHAP! DON’T DO THAHAHAHAT!”

“This is your last chance to submit to my demands of no longer being lazy before I unleash my special attack, brother!” Papyrus warned cockily.

“NOHOHOHO! I-I WOHOHOHON’T DO IT!”

“VERY WELL!” With a devilish grin, Papyrus stopped tickling. Without giving Sans a chance to properly catch his breath, the shot out his arms to grab a hold of his ankles.

Sans’ eye sockets immediately widened, his eternal grin lowering until the beginning of a frown was noticeable, and his facial expression was struck with fear. “P-PAPYRUS, DON’T YOU DARE!”

“Oh, I dare!” the younger brother cackled. He climbed up on the couch to sit on his legs, keeping his feet in place, and whipped off his fluffy pink slippers with ease. He then proceeded to glide and scratch his fingers along the smooth surface of Sans’ soles.

Sans’ frown immediately shot right back up to a large hysterical grin as he laughed loudly, his body convulsing uncontrollably. “WAHAHAHAHAHA! OH, MY GOD, STAHAHAHAHAP!”

“Too late now, brother!” Papyrus laughed with an evil smirk. He continued to tickle his soles, as well as heels and arches, which just made Sans’ squeals even louder and more high-pitched.

“STAHAHAHAHAP! I CAN’T TAHAHAHAHAKE IT! AHAHAHAHA!”

“Oh, I haven’t even hit the sweet spot yet...” Papyrus chuckled. On cue, he glided his hands up to Sans’ bony toes and proceeded to scratch and scribble under and between them.

Sans’ eye sockets flew wide open and tears were practically flying out of them and down his cheeks, which were deep blue in a massive blush. He was thrown immediately into hysterical screams and shrieks as he bucked and thrashed around, doing absolutely anything and everything to try and shake his younger brother off

“WAAAAAAHAHAHAHAHA! NOT THERE, NOT THERE! PLEHEHEHEHEASE!”

“Give in now and this will all be over!” Papyrus cackled as he only picked up the tickling pace. He smirked as Sans attempted to slap the back of his battle body, but his harmless attacks were weakened by his uncontrollable hysteria.

“PLEHEHEHEHEASE STOP, PAPYRUHUHUHUS! PLEHEHEHEASE! AHAHAHAHA!” the older brother wailed as he continued his fruitless slaps on Papyrus’ back.

“I can do this aaaaall day if you so desire, Sans,” Papyrus chuckled, tickling the tops of his toes now. “If that is what you wish, I suppose I can be the better brother and help you out, unlike a certain brother who won’t do the same.”

This was the absolute last straw. The tops of his toes were _way_ too ticklish for Sans to stand for even half a second. He shrieked with laughter and threw his head back, finally deciding to swallow his pride.

“OKAY, OKAY, I’LL STAHAHAHAHAP BEING LAZY! JUST PLEHEHEHEASE STOP!”

“Are you suuuuure?” the younger brother smirked as he tickled the sweet spot even faster, giggling as his older brother squealed silently.

“YESYESYESYESYESYESYESYES!” Sans nodded his head rapidly, tears flying in all directions. “PLEASEPLEASEPLEASEPLEASEPLEASE!”

“Okay, I suppose I could show some mercy now.” Papyrus lifted his hands away and stopped tickling, finally allowing Sans to breathe. Although he lacked the lungs, the older brother still felt completely out of breath.

Papyrus stood up and slipped his red gloves back on with a confident smirk. “You see, brother? Whether it be comforting you or getting what I rightfully deserve through tickle torture, the Great Papyrus is always victorious!”

“Yeah... Remind me... to never d...doubt that again...” Sans panted, laying limp on the couch as he struggled to recollect himself. Once he caught his breath, he sat up and slipped his slippers back on over his feet. “Well... Let’s go do those dishes now.”

“Glad to see you helping me, Sans, even if it was persuaded through drastic means.”

Papyrus helped Sans up to his feet, which still tingled and made it difficult to even wear the fuzzy slippers, and the two made their way into the kitchen.

“Boy Papyrus, you sure did put me in one hell of a **ticklish** situation back there.”

“SANS, FOR CRYING OUT LOUD!”


	2. Sans' Revenge

“Hey, Papyrus, do you know where I put the hot dogs? The human took the last twenty-nine of ‘em after stacking them on their head.”

No response.

“Papyrus?”

Sans scratched his skull in confusion. Pulling his head out from the tall cabinet under the sink, he walked into the doorway and peeked into the living room, only to find his younger brother Papyrus was nowhere to be seen. This definitely took Sans by surprise. Usually the euphoric skeletal monster was watching MTT at this time. But lo and behold, the couch was empty and the TV was turned off.

“Hey, bro?” Sans called out, walking into the living room and looking around. He noticed his pet rock to his right and was shocked to find no sprinkles on it. Or rather, no added sprinkles. Papyrus would usually feed it long before now. There wasn’t even a new sticky note with an irritated message next to his sock he still to this day refused to move.

Something strange was going on here, that’s for sure. Where on earth was Papyrus?

A sudden thought flashed through Sans’ mind, causing his magic to begin to spark upon reflex. What if something happened to him? What if Frisk... What if they...

A loud snort startled the skeletal monster out of his dark thoughts, and his magic was quickly extinguished. He recognized the noise to belong to Papyrus – he felt almost as if he were going to pass out he was so relieved – and detected the source to have come from his bedroom.

“Oh, I see now,” Sans chuckled to himself, placing his hands in his jacket pockets and allowing his muscles – or lack thereof – to relax. The younger brother was working so very hard at making sure the house was kept up with. Things have been made harder with Sans’ constant lounging around and pretty much getting in his way of work. Papyrus was always up and running to keep the house as neat and tidy as possible if he wasn’t cooking spaghetti, recalibrating puzzles, or training with Undyne. The poor monster must’ve passed out from exhaustion a while ago while Sans was out taking a break at his station in hotland.

The older brother decided to walk up the stairs – groaning dramatically with each step – and make his way quietly into his brother’s room to check up on him. Papyrus hadn’t bothered removing his battle body to change into his pajamas before crashing into his race car bed; he wasn’t even under his covers, he was splayed out all over his bed. Sans couldn’t help but laugh to himself. His brother was such a little goofball sometimes.

A new idea flashed through his head, causing his eternal grin to stretch up into a mischievous smirk. He remembered very well of what had happened about a month ago: Papyrus had tickled him in an attempt to make him cut his lazy habits and work alongside him. Naturally, things went back to the way they were, but only after a full week; Sans did not want to go through that kind of experience again. He was grateful every day since then that Papyrus hadn’t tried tickling more sense into him as of yet.

Now Sans finally found the perfect opportunity to get back at his brother.

The skeletal monster’s left eye began to glow blue as his powers were activated, and he used his magic to pin Papyrus down on his bed with his arms held above his head. He then walked up to his side and inhaled deeply before blowing a strong raspberry directly in the center of his spine.

The reaction was immediate. Papyrus’ eye sockets flew wide open as he let out a loud gasp, and once his mind got a grasp of what was going on he let out a squeal followed by hysterical laughter.

“AAAAAHAHAHAHAHA! WH-WHAT’S GOING OHOHON? STAHAHAHAP!”

“Hey, there, little bro,” Sans smirked. “Had a nice nap?”

“S-Sans? What’s going on?” Papyrus began to struggle, but his strength was no match for Sans’ magic. “Why are you using your powers on me? Sans, let me go!”

“I don’t think so, buddy. I’ve been waiting forever to get back at you for your own little stunt, and now that I have the opportunity I’m not just gonna pass it up.”

“That was a month ago!” Papyrus cried, his voice rising with panic. “I thought you’d gotten over that!”

“Then I guess you don’t know me as well as you think.” Without giving Papyrus a chance to respond, he began gliding his fingers up and down his spine, chuckling as it twitched and squirmed.

“N-NYAHAHAHAHA! SANS, STAHAHAHAP!” Papyrus giggled profusely. “TH-THAT TIHIHICKLES!”

“No kidding,” Sans replied with an amused snort. He began to playfully drum his fingers against Papyrus’ spine, sliding his hands up and down to cover the entire backbone.

“EHEHEHEHE! L-LEAVE ME ALOHOHOHONE! IT’S TOO MUHUHUCH! AHAHAHAHA!”

Sans chuckled as he stopped tickling, allowing his younger brother a chance to catch his breath. “Boy, I knew you were ticklish, but I didn’t know you were downright intolerable to it.”

“I-I am...” Papyrus breathed. “So please stop...”

“Nah, I have a better idea: I’ll keep tickling you until you build up the endurance for it!”

“S-SANS, N-AAAGH! AHAHAHAHAHAHA!” The younger brother was cut off as Sans resumed his tickling on his spine. He tried to squirm his backbone out of reach, but those tickly fingers always found a way to catch up. “STAHAHAHAP THAT! PLEASE, BROTHER! EHEHEHEHE!”

“Boy, seems like I really am **tickling your funny bone** , huh?” Sans snickered as he tickled Papyrus’ ribs through his battle body. “What’s wrong, bro? Can’t handle the ticklish **Sans-ations**?”

“SANS, STAHAHAHAP!” Papyrus shouted, tugging at his arms in an attempt to protect his torso; Sans’ magic held fast however. “DON’T MAKE PUHUHUNS! YOU’LL MAHAHAHAHAKE THINGS WORSE! AHAHAHAHA!”

“Don’t think I will, these puns are pretty **humerus**.” Chuckling as he continued tickling Papyrus’ ribs, the older brother inhaled before blowing another raspberry on his spine, causing the younger skeletal monster to shriek in hysteria.

“AAAAAAHAHAHAHAHA! NOT THAHAHAHAT! PLEASE STOP, NYAHAHAHAHA!”

“Nah, I think you like it. Do you like it, baby bro? Does the widdle baby bones like the tickles?” Sans began to tease in a baby tone as he began tickling down his femur bones, past his knee caps, and down his tibia and fibula bones, making his little brother squeal and giggle all the while, until he reached his boots. Smirking, he began to slowly remove them.

“N-NO, SANS!” Papyrus gasped, struggling to yank his legs away. “Don’t tickle my feet, please! I’m sorry for tickling you before! Please let me go, brother, PLEASE!”

“Looks like the Great Papyrus is finally learning the true meaning of **de-feet**!” Sans laughed. He pulled off his younger brother’s boots and immediately began skittering his fingers across his smooth bony soles.

Papyrus’ eye sockets widened in his trademark bug-eyed expression as he let out a scream of laughter before breaking into uncontrollable thrashing and cackling. His feet were way too ticklish for him to stand for long, and already he found himself unable to utter many words through his hysteria.

“S-SA-HAHAHAHAHA! PLEASE! NO-HAHAHAHA! NYAAAHAHAHA! STAHAHAP IT!”

“Tickle, tickle, tickle, baby bones!” Sans teased as he began tickling under his brother’s toes. “I’m sure you’ll keep this special **memen-toe** for a long while, hehehe!”

“NYAAAAAHHH! STAHAHAHAHAP IT!” Papyrus wailed, tears falling down his bright orange cheekbones; he began to fall into silent laughter, his body overwhelmed by the strong ticklish sensations. “PLEHEHEHEHAHAHA! C-CAHAHAHAN’T TAKE IT! AHAHAHAHAHA!”

Sans chuckled a bit, giving his feet one last good tickle – causing Papyrus to let out a silent squeal followed by a loud snort – before finally stopping. Papyrus fell limp with exhaustion as he struggled to catch his breath, giggling weakly over the ghost of the tickles.

“Hehehe, how’d you like that, bro?” Sans grinned smugly at his younger brother. You gonna pull off that little stunt of yours again?”

“N...No...” Papyrus heaved. “I won’t... Not if you’re... gonna retaliate... like that...”

Sans gave Papyrus a sympathetic smile as he subsided his magic, releasing his limbs from their grasp. Papyrus gently pushed his older brother off once he found he could move again.

“Get off me, lazybones,” he growled affectionately. “Sheesh, you can be so annoying sometimes.”

“Hey, that’s my job as your older brother,” Sans retorted with a shrug. “Anyway, I’m guessing that session left you pretty exhausted, so I’ll let you get back to sleep. Perhaps we can head on over to Waterfall later on and solve those new puzzles Undyne’s been telling me about.”

“That would be magnificent!” Papyrus exclaimed excitedly. His sudden euphoric burst of energy was evaporated by a tired yawn, and Papyrus curled up in his bed, smiling as Sans draped the blanket over him. “I love you, brother.”

“Love you, too, Pap,” Sans smiled softly, giving him a loving pat on the head. “Sweet dreams.”

Once Papyrus fell into soft snores, Sans quietly backed out of the room, turning off the light, and closed the door behind him.


End file.
